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71.
The aim of the study was to evaluate differences in the relationship between peripheral diabetic neuropathy and microvascular reactivity in type 1 and type 2 diabetic patients. Twenty-eight type 1 and 37 type 2 diabetic patients were included in the study. Control groups consisted of 18 and 25, age and body mass index matched healthy persons. The presence of peripheral neuropathy was estimated by vibration perception threshold higher than 20 V evaluated by biothesiometry. Microvascular reactivity was examined by laser doppler fluxmetry using postocclusive reactive hyperemia and thermal hyperemia. The following variables of vascular reactivity were examined: peak flow after occlusion as a difference between maximal and basal perfusion (PORH (max)), mean velocity increase during postocclusive hyperemia (PORH (max)/t (1)), peak flow during thermal hyperemia (TH (max)) and the mean velocity increase in the perfusion during thermal hyperemia (TH (max)/t (2)). These parameters are expressed in perfusion units (PU) or in perfusion units per second (PU . s (-1)). The microvascular reactivity in type 1 diabetic patients without evidence of peripheral neuropathy was comparable with that in healthy persons and it was significantly higher than in type 1 diabetic patients with peripheral neuropathy in all tested parameters (PORH (max): 64 [40; 81] PU vs. 24 [17; 40] PU, p < 0.001, PORH (max)/t (1): 5.41 [2.69; 8.18] PU/s vs. 1.21 [0.69; 2.5] PU/s, p < 0.001, TH (max): 105 [77; 156] PU vs. 56 [46; 85] PU, p < 0.001 and TH (max)/t (2): 2.48 [1.67; 3.33] PU/s vs. 0.87 [0.73; 1.06] PU/s, p < 0.001). On the contrary, no difference in the microvascular reactivity parameters was found between type 2 diabetic patients with and without neuropathy (PORH (max): 48 [30; 60] PU vs. 49 [36; 57] PU, NS, PORH (max)/t (1): 3.46 [2.15; 5.19] PU/s vs. 3.29 [2.45; 4.8] PU/s, NS, TH (max): 95 [78; 156] PU vs. 97 [73; 127] PU, NS and TH (max)/t (2): 1.45 [0.95; 2.84] PU/s vs. 1.37 [1.12; 1.95] PU/s, NS). In both these groups microvascular reactivity was comparable with that estimated in the age and BMI matched healthy persons. An inverse relationship was observed between microvascular reactivity and vibratory perception threshold in type 1 diabetic patients, but it was not true in type 2 diabetic patients. We suppose that the pathogenesis of neuropathy and impaired microvascular reactivity may be differently influenced by metabolic factors in type 1 and type 2 diabetic patients.  相似文献   
72.
Choledochojejunostomy (CJS) is commonly used for biliary reconstruction in liver transplantation for primary sclerosing cholangitis (PSC). We alternatively performed choledochoduodenostomy (CDS) and side-to-side choledochodocholedochstomy in a large cohort of patients. Fifty-one patients with PSC, transplanted between 1988 and 2000, were analyzed retrospectively. Biliary reconstruction was CDS in 25 (49%), CJS in 20 (39%) and CC in 6 transplantations (12%). Biliary leaks occurred in the early follow-up (< or =41 days) only in CDS patients (20%). However, in the late follow-up (>4 months), stricturing of anastomosis was found once in CDS (4%) and CJS (5%). Later (>9 months), intrahepatic bile duct strictures were diagnosed in four CDS (16%), one CJS (5%) and one CC (17%) patient(s). In 48% of CDS (12/25), 60% of CJS (12/20) and 17% of CC (1/6) at least one incidence of cholangitis was observed. Overall, biliary complication rates were significantly higher in CDS (40%) than CJS (10%) and CC (17%); of those none in CC and 12% in CDS were anastomosis-related. Graft/patient survival showed no significant differences among groups. Based on our results we consider CJS the standard method for biliary reconstruction in PSC; however, in selected cases where CJS is difficult to accomplish because of previous surgery or for retransplantation, CDS may present an alternative technique.  相似文献   
73.
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.  相似文献   
74.
慢性阻塞性肺疾病中西医发病机制的研究进展   总被引:3,自引:0,他引:3  
慢性阻塞性肺疾病(简称慢阻肺,chronic obstructive pulmonary disease,COPD)是一种常见的呼吸系统疾病,发病率高,在湖北、北京和辽宁三个地区农村102230名成年人调查发现,15岁以上人口COPD的发病率高达3%。COPD呈缓慢进行性发展,严重影响人们的劳动能力和生活质量。但以往对此病重视不够,或仅限于急性加重期和疾病晚期的研究,忽视了疾病发展早期的预防和治疗。虽然国内外均制定了相应的治疗规范,但目前的措施尚不能有效阻止COPD患者肺功能的下降。所以可以说目前没有确实有效的疗法。主要原因是其发病机制尚不清楚。因此将近几年COPD发病机理的某些研究进展综述如下,以期在此基础上研究开发出相应的治疗药物。  相似文献   
75.
1998~2004年本所共收治急性血吸虫病引起免疫复合物肾病患者15例,报告如下。  相似文献   
76.
目的:综合分析近年来国内外神经修复用导管材料以及制备方法的研究近况。资料来源:应用计算机检索ElsevierScience1996-01/2005-12有关神经修复及神经导管方面的文献,检索词分别为“nerveconduit,nerveguide,nerveregeneration”,限定文献语言种类为English。同时计算机检索清华数字期刊库、万方数据库1996-01/2005-12有关神经修复及神经导管方面的文献,检索词为“神经修复,导管”,限定语言种类为中文。资料选择:对检索到的神经再生、神经修复及神经导管方面的相关信息进行整理,选取针对性强的文章。同一领域的文献则选择近期发表或权威杂志的文章。资料提炼:共收集120篇关于神经修复、神经导管的文献,纳入23篇符合标准的文献。资料综合:用神经导管桥接断离神经是神经修复的重要方法之一,制备神经导管的材料按其降解性能分为生物不可降解材料和生物可降解材料,任何一种材料都有其优缺点,发展复合材料将是制备导管的主要方向。结论:虽然影响神经再生的因素还有许多,如神经生长因子、雪旺细胞等,但是新型的导管及制备方法将会有利于神经修复进一步发展。  相似文献   
77.
The purpose of this work was to investigate the use of an intravascular contrast agent to determine perfusion kinetics in skeletal muscle. A two-compartment kinetic model was used to represent the flux of contrast agent between the intravascular space and extravascular extracellular space (EES). The relationship between the image signal-to-noise ratio (SNR) and errors in estimating permeability surface area product (Ktrans), interstitial volume (ve), and plasma volume (vp) for linear and nonlinear curve-fitting methods was estimated from Monte Carlo simulations. Similar results were obtained for both methods. For an image SNR of 60, the estimated errors in these parameters were 10%, 22%, and 17%, respectively. In vivo experiments were conducted in rabbits to examine physiological differences between these parameters in the soleus (SOL) and tibialis anterior (TA) muscles in the hind limb. Values for Ktrans were significantly higher in the SOL (3.2+/-0.9 vs. 2.0+/-0.5x10(-3) min-1), as were values for vp (3.4+/-0.8 vs. 2.1+/-0.7%). Differences in ve for the two muscles (8.7+/-2.2 vs. 8.5+/-1.6%) were not found to be significant. These results demonstrate that relevant physiological metrics can be calculated in skeletal muscle using MRI with an intravascular contrast agent.  相似文献   
78.
最近提出的关于额叶功能的理论认为前额叶皮质,尤其是其背外侧面在确定适合一项特殊任务的一系列反应中起重要作用,并在选择中使上述反应发生偏差。这些活动事实上是为任何类型的非常规任务而执行,而不考虑内容的差别。本研究旨在通过一项解决“洞察力”问题的测试任务(即火柴杆算术作业),来验证Frith“塑造反应空间”假说的预测效力。从Knoblich等人对健康人不能解决火柴杆问题的解释和Frith关于额叶背外侧皮质作用的理论,作者推导出与直觉相左的预测,即对这些相对复杂的任务,外侧额叶皮质局部损伤的患者可能比1组健康受试者完成得更好。要求35例经CT或MRI扫描证实为单个局部脑损伤的患者(年龄为26—65岁)和23例健康受试者(年龄为34—62岁)完成火柴杆作业。研究结果似乎与理论上的预测相一致,虽然仅有43%的健康受试者能解决最困难的火柴杆问题(“C类”),但是却有82%的额叶外侧损伤患者完成了类似问题(Fisher精确概率检验,P〈0.05)。总之,对Frith和Knoblich等人理论的结合进行了确证。  相似文献   
79.
医学生抑郁情绪与家庭及生活事件的相关性研究   总被引:1,自引:1,他引:0  
目的 探讨医学专业大学生抑郁情绪与家庭及生活事件的相关性,为早期干预提供科学理论依据。方法 采用自拟量表对482名医学专业在校大学生调查,并做影响因素分析。结果 大学生无抑郁或极轻微192人占39.8%;轻度209人占43.4%;中度58人占12%;重度23人占4.8%。生源地、父亲文化程度、专业满意度、人际关系的敏感、学习压力的大小、丧失因子、受惩罚因子和健康适应因子对大学生抑郁情绪的产生有显著影响,而性别、家庭类型和经济情况对医学专业大学生抑郁情绪产生关系不大(P〉0.05)。结论 要重视学生中存在的抑郁情绪问题,采取积极有效措施帮助学生消除抑郁情绪。  相似文献   
80.
弹性绷带在乳腺癌术后应用的效果观察   总被引:1,自引:0,他引:1  
目的 观察弹性绷带在乳腺癌术后应用效果。方法  4 8例乳腺癌根治术后应用弹性绷带包扎为实验组 ,4 5例用普通宽绷带包扎为对照组。然后 ,对两组患者术后并发症进行观察。结果 实验组患者的并发症明显低于对照组 ,两组比较有显著性差异 ,P <0 .0 5。结论 应用弹性绷带包扎 ,能明显减少并发症的发生 ,促进切口愈合 ,使患者术后术侧上肢功能锻炼可以提早进行。  相似文献   
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